Transmitter



R. M. HOPKINS.

TRANSMITTER.

APPLICATION man MAR. 29, I920.

1,898,594. Patented Nov. 29, 1921.

3 SHEETS-SHEET 1.

fi c L INVENTORP Ww./W

R. M. HOPKINS.

TRANSMITTER.

APPLICATION FILED MAR. 29, 1920.

1,398,594. Patented Nov. .29, 1921.

. a snezrs suzir 2.

BY flw -M ATTURNEK R. M. HOPKINS.

TRANSMITTER. APPLICATION FILED MAR. 29, I920- 13985594. Pdtqnted Nov. 29, 1921.

3 SH EETS-SHEET 3.

. fig: Z

Arman); i

UNITED STATES PATENT OFFICE.

RICHARD M. HOPKINS, 0E RUTHERE RD, NEw JERSEY, AssIeNoR' T0 AMERICAN DISTRICT TELEGRAPH COMPANY, OF JERSEY CITY, NEw' JE SEY, A CORPO- RATION OF NEW JERSEY.

TRANSMITTER.

Application filed March 29, 1920. Serial No. 369,585.

T 0 all whom it may concern Be it known that I, RICHARD M. HOPKINS, a citizen of the United States of America and a resident of Rutherford, county of Bergen, and State of New Jersey, have invented certain new and useful Improvements in Transmitters, of which the following is a specification.

My invention relates'to automatic transmitters, particularly such transmitters as are employed in alarm systems and the like, and comprises improvements in the automatic transmitter of my application Serial No. 249,460, filed August 12, 1918. My invention consists in various features of combination and arrangement, as hereinafter described and particularly pointed out in the appended claims.

The object of my invention is to improve the construction of transmitters of the type referred to.

I will now proceed to describe my invention with reference to the accompanying drawings, and will then point out the novel features in claims:

Figure 1 shows a front elevation of the transmitter.

Fig. 2 shows a vertical section of the transmitter, the section being taken just in rear of the front frame-plates of the transmitter. I

' Fig. 3 is a front view of the transmitter proper; Fig. 4 is a fragmentary front View of the transposing mechanism of the trans mitter; Fig. 5 is a fragmentary. perspective elevation of the detent mechanism of the transmitter.

Fig. 6 is a side elevation of the magnetoperated controlling mechanism of the trans mitter, looking from the left of Fig. 2.

Fig. 7 is a side elevation of the transmitting mechanism proper of the transmitter, looking from the left of Fig. 2; and Fig. 8 is a rear view of the controlling cam and spring drum and associated parts, the view being a section on the line of Fig. Fig. 9 is an electrical diagram showmg one system in which the transmitter may be used. A In the drawings, 1 designates a break wheel, and 2 designates a combination of contact springs or pens adapted to be actuated by the teeth of that break wheel to send an alarm. The particular arrangemerit. of contact pens or springs so illustrated forms no portion of the present invention," but is claimed in my application Serial No;

329,730 .filed October 10, 1919. It is designed to operate in accordance with the so-called McCulloh system, whereby signals Patented Nova 29, 1921.

are transmitted both through a metallic loop and through a ground connection, and 1 whereby, in the event of breaking of themetallic loop that loop may be divided by 'operation of suitable switching means at the central station, into two separate ground return circuits. well known, and for present purposes the break wheel 1 and contact pens 2 may be considered an ordinary transmitting arrangement.

3 designates a cam forming a part of the transmitter and which starts to rotate when the break wheel 1 starts to rotate, the rotation of the cam being usually, however, at

a slower rate; in the present instance, the

said cam usually rotates at one-sixth the rotative speed of the break wheel.

4, 5 and 6 designate a contact spring com bination, which may be termed a transpos'ing arrangement. The purpose of this transposing arrangement will be set forth more fully later.

gageja ratchet wheel 21, connected to the first gear of a retarding fan train 12. In the present instance the transmitter shown is Such McCulloh systems arev The transmitter comprises a retard mechanism arranged to be operated by'a magnet arranged to have'its magnet 7 normally de- 1 energized, and when that magnet is energized, the armature 8 is attracted, and

thereby caused to move (in aclockwise direction as shown in Fig. 2) against the influenceof the weight 19, and against the retarding influence of thefan train12; and when the magnet 7, after having been energized, is deenergized, the armature moves backunder the influence of the weight 19, without retarding influence of the fan train, thepawl 20 sliding idly over the teeth ofthe ratchet. wheel 21. But obviously the transmitter" might'be arranged to operate with its magshaft 26 of which carries the break wheel 1.

, armature 8 of magnet 7.

The clock train comprises the usual escape- .ment 27 mounted on the disk 27; which disk carries the usual detent pin 28 normally engaging a corresponding detent pin 29 on a pivoted lever 23, which latter lever has an extension 22 arranged to be engaged at a suitable time by an arm 18 connected to the This arm 18 does not engage extension 22 until the armature 8 has moved through nearly the entire range of its movement under the influence of magnet 7, and when said arm 18 does engage extension 22, it cams or pushes said extension to one side, so moving lever 23 about its pivot, and thereby disengaging detent pin 29 from detent pin 28, thereby permitting the transmitter clock train to run. This transmitter clock train comprises a cam 30 (which in the actual construction shown is also the spring case of the driving spring of the transmitter clock train), and this cam 30 has on its rear side one or more notches 31, one of which normally engages the lever 23. But when lever 23 is moved aside to permit disengagement of detent pins 28 and 29, lever 23 is out of engagement with notch 31, with which it has previously been in engagement, and cannot return to the detent position until the same or another notch of the cam 30 comes opposite the lever 23. When such a notch of the cam does come opposite lever 23, a spring 32, riveted thereto and bearing at its free end against the back plate of the casing, forces lever 23 back into engagement with that notch, the detent pin 29 of lever 23 then coming into position to arrest the corresponding detent pin 28 of the transmitter escapement, and thereupon the transmitter is caused to cease operation. The location of the notch or notches of the cam 30 therefore determines the point at which the transmitter ceases operation. In the construction illustrated the driving spring of the transmitter is proportioned to have capacity to drive the transmitter or gear train for several complete operations. Therefore, in the construction shown, the cam 30 has two diametrically opposite notches 31. Supposing magnet 7 (normally de'e'nergized as above stated) to be energized, and to remain energized for a period sunicient for the arm 18 to engage and trip the detent device 2223, the transmitter gear 7 train will begin to operate, rotating break wheel 1 and cam 3. Let it be assumed that V notch of the cam 30. As will appear from I the electrical diagram, Fig. 9, hereinafter described, the effect of breaking contact between spring 4 and spring 5 is to deenergize magnet 7, so that during the operation of the transmitter and the sounding of the signal, armature 8 is retracted under the influence of the weight 19. lVhen the transmitter comes to'rest, as previously described,

therefore, its parts are in normal condition.

If now the magnet 7 be again energized, for a sufficient period to permit arm 18 to trip the detent 22-23, the transmitter will again begin to operate and the spring 4 (therefore held in contact with spring 6 by cam 3) will be s lifted to 5 by said cam, so deenergizingmagnet 7 and permitting spring 4 to make contact with spring 5; whereby the magnet 7 is again deenergized, so that, when the transmitter has ceased its operations, a further energization' of magnet 7 will again start the transmitter in operation. In this way, successive energization of magnet 7 will cause successive operations of the signal transmitter mechanism, until the driving spring is completely unwound. It is because of the transposing action of the springs 4, 5 and 6 that these successive actuations of the transmitter without resetting thereof, and without rewinding of its driving spring, are possible.

Under various conditions of use of the transmitter above described, it is possible that there may be momentary energization of magnet 7 due to occurrences which do not call for the sending of a signal by the transmitter. For example, if the transmitter be used in' a sprinkler supervisory system, there may be brief closures of the controlling switch of the transmitter due to water hammer or the like, which it is not desired shall cause operation of the transmitter. Also in a companion application Serial No. 369,584, filed March 29, 1920, I have indicated how this transmitter may be used in a burglar alarm system, wherein one or more of the controlling switches may he accidentally actuated, and it is desirable that operation of the transmitter shall be prevented by further actuation of any other controlling switch, or actuation of any other controlling switch of the system. It is here that the retard mechanism of the transmitter is particularly useful; for if, after energization of the magnet 7, that magnet be de energized before arm 18 has moved far enough to trip the detent device, said magnet 7 be deenergized, then the armature 8 will move back under the influence of weight 19, the parts being restored to normal condition without any signal having been transmitted.

Fig. 9 shows diagrammatically one switch in which the transmitter above described may be used. The same reference characters for the various parts of the transmitter shown in this diagram, as are used in the preceding figures, are used in this diagram. 15, 15, 15 are four-point switches of Wellknown type, by means of which switches points a and b, d and 0 may be connected, or alternatively, points a and c, b and d, may be connected. These switches are so connected in circuit 16-17, to each other and to the transposing springs 5 and 6, that two alternative circuit paths are provided from battery 13 through the switches to springs 5 and 6 alternatively; and while the circuit is normally broken at the transp osing springs, operation of any one of the switches 15 will shift the circuit to that spring, 5 or 6, which is then in contact with spring 4, so energizing magnet 7, and starting the retard mechanism of the transmitter in operation. If, before arm 18 of the transmitter has contacted with member 22-23 and released the detent, so permitting the transmitting mechanism to start operation, the same or another switch 15 be operated, the circuit through switches 15 will be shifted to that spring, 5 or 6, which is not in contact with spring 4:, and so magnet 7 will be deenerized, and the parts restored to normal. therwise, the transmitting mechanism will begin to operate after member 18 has tripped member 2223, and will continue operating until another cam-notch 31 is entered by member 23, and the transmitter is brought to rest; and during this period of operation cam 3 will shift spring 4.- so that when. the transmitter is brought to rest, the circuit of magnet 7 will be broken, and the transmitter is in condition for another operation upon further actuation of a switch 15, without any resetting of the transmitter or of switches 15.

In this diagram, 14 is a local signal device, such as a bell or buzzer, circuit through which is closed by springs 9 and 10, operated by arm 11 attached to armature 8,

when said armature first begins to move under the attraction of magnet 7.

The particular alarm system shown in Fig. 9 forms the sub'ect-matter of my compitnion application, erial No. 369,584- filed arch 29 1920, and so is not claimed herein.

What I claim is 1. In a transmitter such as described, the combination of transmitting mechanism comprising a normally wound driving spring and a spring drum therefor constituting also a controlling cam, detent means for said transmitter comprising a detent member which alSO engages and is controlled by said cam, a magnet, an armature therefor, means operated by said armature for actuating said detent means, and circuit transposing means connected to said magnet, said transposing means being operated by the initial movement of said transmitting means.

2. In a transmitter such as described, the I combination of transmitting mechanism tending normally tooperate and comprising a controlling cam and a detent pin, a detent lever engaging and controlled by said thereby for releasing said detent, and circuit transposing means operated by said transmitting mechanism upon its initial movement and operatively connected to said magnet to so change the magnetic condition of said magnet, upon operation of said transmitting mechanism, that the detent may opcrate to bring the transmitting mechanism to rest upon the conclusion of a cycle of o erations, and that the transmitter may e then in condition for further operation, without resetting, upon further change of magnetic condition of said magnet.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

RICHARD M. HOPKINS.

"Witnesses:

CATHERINE J. FLEMING, DOUGLAS P- FOWLER. 

